Oracle : ALTER TABLE: Add Columns

Syntax:

ALTER
TABLE

    table_name

ADD(

    column1 datatype1 constraint1,

    column2 datatype2 constraint2,

    column3 datatype3 constraint3

);

ALTER
TABLE

    emp

ADD(

    designation VARCHAR2(100) UNIQUE,

    rank NUMBER
NOT
NULL

);

This will add 2 columns to the table 'emp' named 'designation' and 'rank' with given constraints and data types